I agree with you on this much: If God doesn't allow it to be done, then it won't be done; just like how God would not let Satan touch Job's person the first time Satan brought misfortune to Job, and also, with the next time Satan brought misfortune to Job, God wouldn't let Satan take Job's life.
I disagree, however, because I know God prohibits things such as in the Commandments and the Law, yet people still violate the Commandments and the Law. Somehow, sin occurs without God allowing it to occur.